Twice a year in the Gulf of Mexico rays migrate. About 10 thousand stingrays swim from the Yucatan Peninsula to Florida in the spring and back in the fall.
In the resort town of Skagen you can watch an amazing natural phenomenon. This city is the northernmost point of Denmark, where the Baltic and North Seas meet. The two opposing tides in this place can not merge because they have different densities.
In the Chinese province of Shandong is a bridge across the Gulf of Jiaozhou. The bridge length over 36 km is calculated for eight car lanes, and is the longest sea bridge in the world.